S. Parasuraman and  Ler Shiaw Pei,  Bio-mechanical Analysis of Human Joints and Extension of the Study to Robot.   journal   = {International Journal of Mechanical and Mechatronics Engineering}, [online]. World Academy of Science, Engineering and Technology.
    March 2008, vol. 15(3). 236 - 241
    [viewed 25 April 2024]. Available from: https://publications.waset.org/pdf/11605.